Web Forms :: New Entries Added To Listbox Not Appearing After Postback?
Oct 22, 2010
I have added a listbox, and on page load I populate it with a few items. Then I have added Javascript code so that the client can click a button to add more items to the listbox. But when the page is postedback I am only left with the items that were loaded from the page load....
Is this the way .net operates?
I was reading that if I need to get all the items in the listbox, I will need to add a hidden field and write out the items in a CSV format, and then use that hidden field to work out the items in the listbox..
I am having 3 ListBoxs(LB1,LB2,LB3).In LB1 I am binding the names of Courses through database.The code is shon below...
da1 = new SqlDataAdapter("SELECT COURSE_ID,COURSE_NAME FROM Course_Mst", con); DataTable dt1 = new DataTable(); da1.Fill(dt1); lstCourse.DataSource = dt1; lstCourse.DataValueField = "COURSE_ID"; lstCourse.DataTextField = "COURSE_NAME"; lstCourse.DataBind();
Whenever I select particular course in LB1 all the content related to that course will be binded in LB2.The code is shown below.....
protected void LB1_SelectedIndexChanged(object sender, EventArgs e) { da2 = new SqlDataAdapter("SELECT SPEC_ID,SPEC_NAME FROM SPEC_TRANS WHERE COURSE_ID="+Convert.ToInt32(lstCourse.SelectedValue)+"", con); DataTable dt = new DataTable(); da2.Fill(dt); lstSpecilization.DataSource = dt; lstSpecilization.DataValueField = "SPEC_ID"; lstSpecilization.DataTextField = "SPEC_NAME"; lstSpecilization.DataBind(); lstSpecilization.Focus(); }
I am having a ADD button.In LB2 I can select multiple items.When I select multiple items in LB2 and click on ADD all the selected items will be binded into LB3.The code is shown below...
protected void btnAddCourseDetaisl_Click(object sender, EventArgs e) { for (int intLoopIndex = 0; intLoopIndex <lstSpecilization.Items.Count ; intLoopIndex++) { if (lstSpecilization.Items[intLoopIndex].Selected) { ListItem li = new ListItem(lstSpecilization.Items[intLoopIndex].Text, lstSpecilization.Items[intLoopIndex].Value); LB3.Items.Add(li); } } }
My problem is when I select a item from LB2 and click on ADD the selecteditem is added to LB3 but if I select the same item and click on ADD the items are again added to the LB3.I want to prevent this.Pls respond me ASAP.
i want to send a some form entries resulting in a postback to be mailed automatically with my gmail account to the target mail id entered by the user with asp.net - c#?
The scenerio is I have a UserControl. This user control will create dynamically ListBoxes if the given List's count > 0. The controls are adding dynamically, there is no problem with adding them, but the event handler is not adding. If I select an item in first listBox, the secondListBox will be added dynamically, and items will add dynamically too. First listBox appears, but the selectedIndexChanged event handler doesn't work. What can be the problem with my code?
I have an asp.net listbox with 15 rows and auto postback when the selected item is changed. This works as expected but, when the form is re-loaded, IE scrolls the list so that the last selected item is now the top visible item in the list. This produces a confusing/jumpy effect for the users and makes the listbox more difficult to use than it needs to be.
Is there any way to get the list scroll position to stay as it was before the postback? i.e, if I select an item from the middle of the listbox, the listbox is scrolled to the same point after postback.
What I'm trying to achieve/plan, is whereby a page loads with a set of inputs, e.g. TextBox, Radio List etc. Taking TextBox as an example, there is a button for the user to "Add" another textbox to the page (in the same group), e.g. Member1, Member2, Member3 etc etc.
Two questions:
I could add these with Javascript, however the resultant "save" on postback would not get these inputs? If so, how? The form needs to work without Javascript as well, so postback to dad another control is fine, however if I click the "add" button again, it will only ever add one control.
I must be doing something wrong, but this makes sense to me. I have a Listbox loaded with tons of items from a datasource. A user clicks one of these items it grabs the selectedindex (an integer) and stores it in a HiddenField (works fine).
Now when the page does a complete a refresh (after postback) I want the ListBox to go back to that selectedindex that is in the HiddenField. Problem is, it seems that after postback the HiddenField is empty? Then I thought about storing the value in an Integer variable in code, but that is simply coming up as a zero at all times.
Question 1: What is the best/simplest way to do this?
Question 2: How?
I am currently grabbing it on selectedindex change
I have a page with 4 fixed Tabs. Tabs 1 and 2 are always in position 1 and 2. However, the users are allowed to create their own tabs and add their own html content. I do this by creating a new tab in codebehind and inserting it into the tabcontainer AFTER the frist 2 and before the last 2 tabs. There could be several of these. EX: "F1 | F2 | U1 | U2 | U3 | F3 | F4" where F is a fixed tab and U is a custom tab.
As long as ALL tabs are visible then everything works fine after postbacks.
Based on user settings I sometimes hide fixed tab 1. Everything loads fine the first time. However, on postback The content on fixed tab 4 (always the last tab) is displayed on the bottom of EVERY tab (fixed or custom). It is still displayed in fixed tab 4.
A little background on the code:
Since the tabs are added dynamically they do not exist on postback and must be re-generated every time. This is done in Page_LoadComplete. I have tried it on PageLoad and it behaves the same way.
If I do not re-generate the pages on post back then the problem goes away - as do the custom tabs.
The only thing I could find was from last year, and was supposedly fixed (http://www.codeplex.com/AjaxControlToolkit/WorkItem/View.aspx?WorkItemId=16321
I made a web part use ASP.NET. There are a listbox and two buttons on it. When you click the Button A, it would add a new item into the listbox.When clicking the Button B, it would postback the list items data. But when you click the button B, the number of listbox number becomes twice.
@Html.ListBoxFor(m => Model.Runtimes, new SelectList(Model.Runtimes, "Id", "Runtime"))and when I access the page all the runtimes in the model are displayed as expected. I also have a button in my view with a jQuery function attached to it: btnIntermediate.click(function () { timer.addIntermediate(function (runtime) { url = "/Timer/SaveRuntime/?runtime=" + runtime; $.get(url); }); });It saves the runtimes to the model. My problem is how to update my Listbox with the new entry in the model without triggering a postback(since it will stop my timer)?I'm
I'm having trouble processing a listbox after selecting some items from it. In my markup, the listbox is contained within an asp:panel and is populated during page load in the codebehind. That part works fine.
It's when I select various items and submit that I have trouble. My handler loops through the listbox items but doesn't see any as being selected. I'm not sure why.
In my btnUpdate_OnClick handler I can't see any listbox items that are marked as selected. I assume something strange is going on with respect to postback and the panel?
I have a dropdown listbox whose datasource is a dictionary.
When I have added items to the list and try to select an item from the list, the item I selected does not get the focus. And this comes when I changed the property autopostback to true.
Here are some of the codes which are relevant to it.
I'm trying to add a JavaScript function to show all selected items from a ListBox as concatentated strings in a Label on the page. It's needed because AutoPostBack="true" will cause the ListBox to scroll all the way back to the first selected item.
So this code works:
<script type="text/javascript"> function Updatelist() { var sel = document.getElementById('<%=lstbxStuff.ClientID%>'); var lbl = document.getElementById('ctl00_cph_lblSelectedStuff');
[Code]....
Unfortunately I still need the code behind SelectedIndexChanged delegate. Is there a way to use both of these without doing a PostBack? When I set AutoPostBack="false", my delegate never seems to be reached.
I am designing a program that will let me enter the name of an item to swap and adds the swap to an array list when a button Add is pressed. Once the item is added to the array list a Sub Procedure should be called which displays the contents of the array list in a list box.
The system will also allow me to remove items from the array list using a Remove button
followed by updating array list.
I have done some part which puts item into the listbox1 which i named lstSwapList.I would need some assistance on the Sub Procedure to display the Value or Description on the other listbox2 which i have also named lstContent,if a value is selected from the listbox1.
I would also want to know how to update the Listbox content,However i hv added a sample of the way i guess it may be.
Any complete solution from anybody on the Sub Procedure and the Update Swap procedure will be greately appreciated.
The script below is what i have done so far.
Partial Class _Default Inherits System.Web.UI.Page Protected Sub lstContent_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles lstContent.SelectedIndexChanged End Sub Protected Sub lstSwapList_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles lstSwapList.SelectedIndexChanged End Sub Protected Sub btnAddSwap_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnAddSwap.Click Dim SwapValue As String = "Sixty Pounds" Dim Counter As Integer = 8 Dim SwapN0 As Integer lstSwapList.Items.Add(SwapValue) lstSwapList.Items.Add(Counter) lstSwapList.Items.Add(New ListItem("300", "1")) lstSwapList.Items.Add(New ListItem("ASP.Net", "2")) lstSwapList.Items.Add(New ListItem("Programming", "3")) SwapN0 = lstSwapList.SelectedValue For Counter = 0 To -1 SwapN0 = lstContent.Items.Count Next End Sub Protected Sub btnDeleteSwap_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnDeleteSwap.Click lstSwapList.Items.Remove(lstSwapList.SelectedValue) End Sub Protected Sub btnUpdateSwap_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnUpdateSwap.Click End Sub End Class
======================================= Sub UpdateSwap(ByVal valueA As String, ByVal ValueBAs String, ByVal ValueC As Integer, ByVal ValueD As Date)
I have two list boxes, one has a list of available users (about 1500 items) and the other is blank. There is a button to add the seleted items from the first list box to the second one. Both of these listboxes are within an update panel and for some reason it takes over 20 seconds for the items to show up in the second listbox.
Is this normal? Is there an alternate, faster way of doing this?
I have the following list of projects WebUI (WebSite) , DataAccess (ClassLibrary) , LogicLayer(ClassLibrary). Those of the project are purposively crated separately.But my scenario is, need to create only one solution file, then add all of the above projects under this solution file. So that i can be easiy interacted and changes can be made by opening solution file only instead of opening each project individually.
Simply all of the layer projects are under one roof means one solution. I tried it by adding solution first, then i added already existed project into this. But once after added already existing project the solution icon vanished by showing the icon of recently added project. By this way I could not add another project into this section too.Hope this is the way the basic real-time projects are created; to achieve the centralized control over architecture based projects.
I am getting an error whenever I try to get the first character from a textbox control when nothing was entered into it. So, I need to be able to check if there are any entries in a textbox before trying to get the first one.
if i enter the value in the textbox based on the textbox value it should go to that page.for eg: i've one textbox,one buttonand three forms namely plant.aspx,green,aspx,companies.aspxif i enter the text as "what is plant" into textbox and click the button the it should search the word plant and redirect it to plant.aspx form.if i enter the text as "what actually green is" into textbox and click the button the it should search green and redirect to green.aspx form.
All i did is added an existing webform from vs 2003 project to vs 2008. with Listbox1 control this error is appearing. value of type system.web.ui.webcontrols.listbox cannot be converted to "myprojectname.listbox"
i also have the control defined on the top: Protected WithEvents Listbox1 As System.Web.UI.WebControls.ListBox I have converted lot of pages which were used in vs 2003 to vs 2008 without any problem, also tried to right click teh webform and go to code gen file , but the file is not coming up.
I am currently working on a project where I am trying pull a list of entries from an Oracle database depending on a selection that is made by the user via a Drop Down list. Then I want provide a user with a list of options that they can select that is related to the drop down option that they have selected. For Example:
First Drop Down from database: Honda, BMW, Ford
If user selects:
Honda -- options that are available in the separte table in the database for this entry are -- Type, Engine Size, Colour
BMW -- options that are available in the separte table in the database for this entry are -- Colour, Wheel Trims, Extra's
Ford -- options that are available in the separte table in the database for this entry are -- Extra's
What I wanted to do is have a form displayed to the user where thy can say select a car eg. "BMW" and then on the change of that drop downs index the site will do a call back and retrieve the entries for the BMW options in the seperate tabel, these being Colour, Wheel Trims, Extra's. Then it will put these details in a DataSet and then i wanted to create a new text box or input field for the users to enter details in. I have tried the below code with no success as I get an error on my for loop of looking through the options DataSet.
